Program Examples:Homing
The following example demonstrates how to issue a homing procedure on all the axes.
A "For Loop" iterates over the axes that are attached to motion drives, sets the desired homing parameters and invokes EC_SLAVE_HOME to start the homing procedure.
 | NOTE |
|
The homing parameters must be set in "Drive Units", therefore the user values are converted to drives units by multiplying them by the relevant motion factor and by a factor of 1000 to scale from seconds to milliseconds. |
'**************************************************************************************************
' File: HOME.PRG
' Purpose: Home all the drives
' Version: 1.00
' Author: Nir Geller
' Global Variables Used: num_Of_Motion_Drives as long - Number of ECat MOTION DRIVES found by EC_SETUP.PRG
' Axes[64] - An array that holds all the axes in the system. Defined in CONFIG.PRG
' History: 9.11.14 - Created
' Description: This program example iterates over the axes and calls homing procedure.
' The homing parameters setting and the homing procedure is CDHD specific
'**************************************************************************************************
'************** Explanation **************
' Before starting the homing procedure the user must set homing parameters in the drive.
' These parameters must be in "drive units", therefore, the desired homing velocity is translated to
' drive units by multiplying it by the velocity factor and by a factor of 1000 in order to scale from
' seconds to milliseconds. The same is done for homing acceleration.
'**********************************************************************************************
Program
dim dHomingFactorFast as double = 0.5
dim dHomingFactorslow as double = 0.25
dim dHomingFactorAcc as double = 0.1
dim dSec2msec as double = 1000 ' this is used to convert from typical user time-units [msec] to typical drive time-units [sec]
dim dHomingVelocity as double = 0
dim dHomingAcceleration as double = 0
dim i as long = 0
' **** Home all the drives ****
for i = 1 to num_Of_Motion_Drives
attach Axes[i]
' **** Set homing parameters ****
' set homing method = 34 (pulse index, positive direction)
call EC_SLAVE_SET_HOMING_PARAMETERS(Axes[i], HOMING_METHOD, 34)
' set homing offset
call EC_SLAVE_SET_HOMING_PARAMETERS(Axes[i], HOMING_OFFSET, 0)
' set FAST homing speed = 10
dHomingVelocity = (Axes[i].VCruise * Axes[i].VFac * dSec2msec) * dHomingFactorFast
call EC_SLAVE_SET_HOMING_PARAMETERS(Axes[i], FAST_HOMING_SPEED, dHomingVelocity)
' set SLOW homing speed = 2
dHomingVelocity = (Axes[i].VCruise * Axes[i].VFac * dSec2msec) * dHomingFactorSlow
call EC_SLAVE_SET_HOMING_PARAMETERS(Axes[i], SLOW_HOMING_SPEED, dHomingVelocity)
' set homing acceleration/deceleration
dHomingAcceleration = (Axes[i].amax * Axes[i].afac * dSec2msec^2) * dHomingFactorAcc
call EC_SLAVE_SET_HOMING_PARAMETERS(Axes[i], HOMING_ACCELERATION, dHomingAcceleration)
call EC_SLAVE_HOME(Axes[i], 120000) ' Homing timeout: 120,000 msec
Axes[i].en = 0
detach Axes[i]
next
End Program
The example corresponds to commit SHA-1: 4fe3c7018de141d855eb556d3e637e0283807314 in GIT.